The present invention relates to a brake pad of a disc brake having at least one friction pad mounted on a pad carrier, and having a locking device arranged on the pad carrier and having a spring element and a securing element. The invention also relates to a corresponding disc brake.
Brake pads of this kind are used in disc brakes for vehicles. In this case, the brake pads are accommodated in pad slots of a brake carrier. A pad slot of this kind is delimited at the sides by “brake carrier horns”.
Normally, the lateral functional surfaces of the brake carrier horns are nowadays situated in a position aligned parallel to one another. This can have the effect that the brake pad tilts against the two brake carrier horns when subjected to shaking and hence that a self-locking effect is obtained, i.e. the brake pad is prevented from climbing out of the pad slot. This relieves the load on the pad hold-down springs and protects the tangential contact areas of the brake pads and those in the pad slot of the brake carrier from wear.
As soon as the above-described parallel alignment of the two brake carrier horns is departed from, the self-locking effect disappears, resulting in increased wear on the components involved.
DE 10 2010 023 143 A1 describes a disc brake for a commercial vehicle and a brake pad for a disc brake, which is fitted with a pad holding spring. At least the pad holding spring of a brake pad on the application side has an elastically deformable securing element at each end which is elastically deformable between the associated brake carrier horn and the brake pad. This embodiment has proven its worth per se but it is regarded as disadvantageous that fitting and, in particular, removal of the brake pads entail an increased expenditure of force and also an additional tool.
There is a continual requirement for increased functional reliability and simplicity of fitting during production and servicing.
It is the underlying object of the invention to provide an improved brake pad.
Another object consists in providing an improved disc brake.
The invention achieves this and other objects by providing a brake pad of a disc brake having at least one friction pad mounted on a pad carrier, and having a locking device arranged on the pad carrier and having a spring element and a securing element. The invention also relates to a corresponding disc brake. The spring element and the securing element of the locking device are coupled positively to one another as two separate parts and can be pivoted relative to one another. A further object is achieved by a disc brake having such a brake pad.
By forming the locking device with two separate parts which are coupled positively and can be moved relative to one another, not only simple fitting but also easy removal of the brake pad are made possible.
A disc brake pad according to the invention includes at least one friction pad mounted on a brake carrier, and a locking device arranged on the pad carrier and having a spring element and a securing element. The spring element and the securing element of the locking device are coupled positively to one another as two separate parts and can be pivoted relative to one another.
A disc brake according to the invention, in particular a sliding caliper disc brake, for a vehicle comprises a brake caliper, a fixed-location brake carrier, which has two pairs of brake carrier horns, by each of which one brake pad is held, and at least one pad holder. At least one brake pad is designed in accordance with the invention, and at least one of the two pairs of brake carrier horns with which the at least one brake pad according to the invention is in contact has a recess, which interacts with the locking section of the locking device of the at least one brake pad according to the invention.
In the installed state of the brake pad, one section of the securing element of the locking device interacts with the recess in the associated brake carrier horn.
In one embodiment, the locking device can be moved out of an unlocked position, in which a locking section of the securing element is accommodated in a recess in the pad carrier, into a locking position, in which the locking section of the securing element projects laterally from the pad carrier in order to interact with a recess in a brake carrier horn of a disc brake to be associated therewith, and back out of said position. In this way, simple fitting during the insertion of the brake pad is possible without the need for an additional expenditure of force or an additional tool.
Further advantageous embodiments of the brake carrier according to the invention are described herein.
In another embodiment, the spring element has a slot extending in the longitudinal direction of the spring element in each end region of a spring body, and the securing element has a body having a slot-type opening, wherein the body is formed at one end with a locking section and is coupled at another end to the spring element. Simple production of the separate parts, e.g. by punching and bending operations, is thus possible.
Provision is made for the spring element and the securing element to be coupled positively in this way by one slot in a coupling section in one end region of the spring element being in engagement with the other end of the securing element. In this way, simple assembly of the parts is achieved.
In another embodiment, it is envisaged that the other end of the securing element, i.e., the end in engagement with one slot in the spring element, has a narrow connecting section, which connects the body of the securing element to a transverse end. The narrow connecting section is accommodated movably in the slot in the coupling section of the spring element. This results in a further advantage of rapid assembly of the locking device.
In another embodiment, the locking device is arranged on an upper side of the pad carrier in a manner which allows it to be removed again in such a way that a projection of the pad carrier is arranged in the slot-type opening in the securing element and a guide projection of the pad carrier is arranged in the slot in the coupling section of the spring element. A further guide projection of the pad carrier is arranged in the slot in the spring element. In this way, very advantageous fitting, removal and reuse of the locking device is possible.
Another embodiment envisages that the locking device is arranged on the upper side of the pad carrier in a manner which allows it to be removed again in such a way that a support end of the spring element, said end being adjacent to the other slot in the spring element, rests on the upper side of the pad carrier in the locking position of the locking device. The coupling section of the spring element rests by way of its underside on an upper side of the locking element and presses the locking element onto the upper side of the pad carrier. In this way, it is advantageously ensured that the locking element can be coupled in a simple and effective manner to the spring element.
In an alternative embodiment, the other end of the securing element, i.e., the end in engagement with one slot in the spring element, has a coupling section having a coupling opening, wherein a section between the body of the securing element and the coupling section is accommodated movably in the slot in the coupling section of the spring element. This is a simple design with parts that are simple to produce.
In another embodiment, the locking device furthermore includes a coupling member, which is connected pivotably to the coupling section of the securing element at a pivoting axis, and which is connected pivotably to a projection on the upper side of the pad carrier at a further pivoting axis. An advantageous positive movement of the securing element around the pivoting axis is thereby made possible.
The upper side of the pad carrier of the brake pad is to be understood to mean the narrow side of the pad carrier, which lies opposite the lower side, which rests in the pad slot. The friction pad is mounted on one of the large-area sides of the pad carrier.
In this case, the coupling member has at least one longitudinal section, which is connected at its ends to respective coupling sections, wherein one coupling section is connected pivotably to the coupling section of the securing element and one coupling section is connected pivotably to the projection. Thus, the coupling member can be of U-shaped design or can be designed as a chain link, for example.
In one embodiment, the locking device is arranged on an upper side of the pad carrier in such a way that a projection of the pad carrier is arranged in the slot-type opening in the securing element, and that a guide projection of the pad carrier is arranged in the slot in the coupling section of the spring element, and a further guide projection of the pad carrier is arranged in the slot in the spring element, wherein the coupling member is connected pivotably to the projection of the pad carrier at a pivoting axis. Thus, the locking device is fixed and guided at defined points on the upper side of the pad carrier.
In another embodiment, the locking device is arranged on the upper side of the pad carrier in such a way that a support end of the spring element, said end being adjacent to the other slot in the spring element, rests on the upper side of the pad carrier in the locking position of the locking device. The coupling section of the spring element is arranged between the first coupling member and the locking element, and the coupling section of the spring element rests by way of its underside on the upper side of the locking element and presses the locking element onto the upper side of the pad carrier. A simple construction is thereby advantageously achieved.
In yet another embodiment, the locking device is arranged on the upper side of the pad carrier in a manner which allows it to be removed again in such a way that the coupling member is formed in a U shape with an axial retention device that can be removed again, and/or that the connection of the coupling member to the projection or to the coupling section of the securing element is designed as a clip-type joint. In addition to the advantage of simple fitting, this also results in simple removal and reuse of the locking device.
In another embodiment, the locking device furthermore has a further coupling member, which is connected pivotably to a bearing end of the spring element, said bearing end being formed with an opening, and which is connected pivotably to a bearing projection on the upper side of the pad carrier. In this way, a defined mobility of the locking device can be achieved.
For this purpose, the further coupling member can be connected to the bearing projection in a manner which allows pivoting and sliding, e.g. by use of a slotted hole.
The further coupling member also has at least one longitudinal section, which is connected at its ends to respective coupling sections, wherein one coupling section is connected pivotably to the bearing end of the spring element and one coupling section is connected pivotally to the bearing projection. Of course, embodiment of the further coupling member as a chain link is also possible.
In yet another embodiment, the locking device is arranged on an upper side of the pad carrier in such a way that the projection of the pad carrier is arranged in the slot-type opening in the securing element, and a guide projection of the pad carrier is arranged in the slot in the coupling section of the spring element, and a bearing projection of the pad carrier is arranged in the slot in the spring element. The coupling member is connected pivotably to the projection of the pad carrier at a pivoting axis, and the further coupling member is connected pivotally to the bearing projection.
In yet another embodiment, it is envisaged that the locking device is arranged on the upper side of the pad carrier in such a way that the support end of the spring element rests on the upper side of the pad carrier in the locking position of the locking device. The coupling section of the spring element is arranged between the first coupling member and the locking element, and the coupling section of the spring element rests by way of its underside on the upper side of the locking element and presses the locking element onto the upper side of the pad carrier. This advantageously simple construction allows effective locking.
In one embodiment, the locking device is arranged on the upper side of the pad carrier in a manner which allows it to be removed again in such a way that the further coupling member is formed in a U shape with an axial retention device that can be removed again, and/or that the connection of the further coupling member to the bearing projection or to the bearing end of the spring element is designed as a clip-type joint. This results in advantageous simple fitting and removal and the possibility of reuse.
In one embodiment of the disc brake, the recess is formed in the manner of an undercut. This allows simple interaction with the locking device.
In another embodiment, the locking device of the at least one brake pad is moved out of an unlocked position, in which a locking section of the securing element is accommodated in a recess in the pad carrier, into a locking position, in which the locking section of the securing element of the pad carrier is in engagement in order to interact with the recess in the associated brake carrier horn when the pad holder is fitted. The locking section of the locking element engages in the undercut-type recess in the locking position.
In one embodiment of the disc brake, it is envisaged that the pad holder moves the locking device of the at least one brake pad automatically out of the unlocked position into the locking position when it is fitted. This is advantageously simple and does not require any further changes to the disc brake.
In an alternative embodiment, at least one separate actuating component can be provided for moving the locking device of the at least one brake pad out of the unlocked position into the locking position. For this purpose, it is possible, for example, to use a spring-loaded rotatable pin with a bayonet catch or, alternatively, a screw.
In the installed state, the securing element is secured against tangential movement by a corresponding contour in the brake pad carrier. This is made possible by the corresponding projections.
The spring element of the locking device secures the securing element against radial movement in the installed state of the brake pad.
The securing element furthermore advantageously forms a travel limitation with a defined play which is free of force in the installed state, thereby ensuring that the movement force of the brake caliper is not increased.
In the installed state of the brake pad, the securing element can lift off counter to the spring force of the spring element in the event of overloading in the locked position and thus advantageously forms an integrated overload safeguard.
The two-part locking device with the spring element and the securing element reduces wear in the region of the undercut-type recess in the brake carrier horn and thus reduces play with respect to the brake carrier horn in contrast to a one-piece spring locking element.
Another advantage is that impermissible wear on the brake pad and brake carrier is prevented or considerably reduced, and this can lead to an extended service life for the components and to longer maintenance or replacement intervals.
Illustrative embodiments of a brake pad according to the invention and of a disc brake according to the invention are shown in the drawings and are described in greater detail below, and further advantages of embodiments according to the invention are also explained. In the drawings: